First recognized in 1870 (Eberth, C. J., Arch. Pathol. Anat. Physiol. Klin. Med., 49:51-63 (1870.), neoplastic meningitis is now being seen with increasing frequency, no doubt reflecting more effective therapy of systemic cancer as well as heightened awareness and improvements in diagnostic tools. Neoplastic meningitis can result from leptomeningeal dissemination of a spectrum of cancers, either arising from the central nervous system, such as medulloblastoma or high grade glioma, or resulting from invasion by lymphoma, leukemia, melanoma, sarcoma, or carcinoma (notably breast and lung carcinoma). Furthermore, the striking incidence in AIDS-related CNS lymphoma (which has a 50% incidence of leptomeningeal spread) suggests that an extensive population in the United States and abroad will require treatment of neoplastic meningitis. Unfortunately, current therapy of leptomeningeal disease is particularly ineffective with external beam radiotherapy and intrathecal chemotherapy, specifically methotrexate, thiotepa, or cytosine arabinoside only providing modest benefits, with mean survival following leptomeningeal tumor spread measured in months (Grossman S. A. and Moynihan T. J., Neurol. Clin., 9:843-856, 1991 1991). Newer therapies are clearly needed for treatment of patients with cancer, especially patients with neoplastic meningitis and other cancers occurring in compartmentalized regions of the body.